Substrate processing device and substrate processing method for carrying out chemical treatment for substrate

ABSTRACT

It is an object to carry out a chemical treatment for a peripheral edge part of a substrate while suppressing an amount of consumption of a processing liquid and a time required for processing. In order to achieve the object, a substrate processing device injects heating steam to a peripheral edge part of a substrate to heat the peripheral edge part when carrying out a chemical treatment for the peripheral edge part of the substrate while rotating the substrate in a substantially horizontal posture. Moreover, the substrate processing device injects a gas from above the substrate toward a predetermined injection target region defined within a range surrounded by a rotating track of the peripheral edge part of the substrate in an upper surface of the substrate, thereby generating, on the substrate, a gas flow which flows from the injection target region toward the peripheral edge part of the substrate.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a substrate processing device and asubstrate processing method for supplying a processing liquid to asubstrate to carry out a chemical treatment such as etching whilerotating the substrate. The substrate to be processed includessubstrates, for example, a semiconductor wafer, a substrate for anoptical disk, a substrate for a magnetic disk, a substrate for amagneto-optical disk, a substrate for a photomask, a substrate for asolar cell, and the like.

2. Description of the Background Art

Although a series of processing steps for a substrate such as asemiconductor wafer have a plurality of film forming steps for forming athin film of a metal, a photoresist or the like on a front surface (“anupper surface”) of the substrate, a film is also formed on a backsurface (“a lower surface”) of the substrate or a peripheral edge partof the upper surface of the substrate at the film forming step in somecases. In general, however, the film formation is required for only acircuit formation region in a central part of the upper surface of thesubstrate in the substrate. In cases where the film is formed on theback surface of the substrate or the peripheral edge part of the uppersurface of the substrate, a thin film formed on the peripheral edge partof the upper surface of the substrate may be peeled by contact withanother device at a subsequent step to the film forming step, and maycause reduction in yield or a trouble of a substrate processing deviceitself.

Therefore, there is proposed a substrate processing device for carryingout so-called bevel etching, that is, previously supplying a processingliquid having its temperature controlled to a peripheral edge part of asubstrate held in a substantially horizontal condition while rotatingthe substrate, thereby removing a thin film formed on the peripheraledge part of a upper surface of the substrate.

For example, the substrate processing device described in JapanesePatent Application Laid-Open No. 2004-6672 serves to supply the etchantfrom the nozzle taking an opposed shape to the central part in the lowersurface of the substrate held in a substantially horizontal condition tothe lower surface of the substrate while rotating the substrate, and tocause the etchant spreading toward the peripheral edge part by theaction of centrifugal force to go around the peripheral edge part of theupper surface of the substrate, thereby etching the peripheral edge partof the upper surface of the substrate.

Moreover, the substrate processing device described in Japanese PatentApplication Laid-Open No. 2008-47629 has the blocking member which isopposed to the upper surface of the substrate above the substrate andserves to supply the processing liquid from the nozzle disposed on theperipheral edge part of the blocking member toward the peripheral edgepart of the upper surface of the substrate while rotating the substratein the substantially horizontal plane, thereby etching the peripheraledge part of the upper surface of the substrate.

However, the devices disclosed in Japanese Patent Application Laid-OpenNos. 2004-6672 and 2008-47629 have a problem in that the amount of theprocessing liquid and the processing time which are required for theetching in the peripheral edge part are increased because thetemperature of the peripheral edge part is reduced due to the rotationof the substrate, resulting in decrease in the etching rate.

In the technique of this type, it is demanded to reduce an etching widthin the peripheral edge part (“end”) of the upper surface of thesubstrate as small and evenly as possible in order to effectivelyutilize, as a device, an area over the substrate which is as large aspossible. In the technical field of manufacture of a semiconductordevice, particularly, it is desired to decrease an etching width of 2 to3 mm in the related art down to 1 mm or less in order to reduce a lossin a peripheral edge part of a wafer which is increased with increase indiameter of a semiconductor wafer, for example.

As a method for reducing the etching width by the substrate processingdevice described in the Japanese Patent Application Laid-Open No.2004-6672, it is supposed to decrease an amount of supply of theprocessing liquid and to increase the rotating speed of the substrate inorder to reduce an amount of wraparound of the processing liquid towardthe upper surface of the substrate. According to the method, although anaverage etching width can be reduced, uniformity of the etching width isdeteriorated, for example, the amount of wraparound of the processingliquid to the peripheral edge part is controlled with difficulty so thata portion to be etched locally and greatly appears. Furthermore, thereis also a problem in that the temperatures of the peripheral edge partand the processing liquid in the peripheral edge part are lowered,resulting in reduction in an etching rate.

In order to decrease the etching width by the substrate processingdevice described in the Japanese Patent Application Laid-Open No.2008-47629, it is necessary to decrease the amount of supply of theprocessing liquid to be supplied to the peripheral edge part of thesubstrate. However, there is a problem in that the etching rate in theperipheral edge part of the substrate is reduced due to decrease in theamount of the processing liquid and reduction in the temperature of theprocessing liquid in a pipe due to the decrease.

These are problems which are not limited to the etching using anetchant, but are caused in general processing for carrying out achemical treatment for a substrate by using a processing liquid having achemical activity (chemical reactivity) varied depending on atemperature (a processing liquid having a reaction rate increased with arise in temperature).

SUMMARY OF THE INVENTION

The present invention is directed to a substrate processing device forcarrying out a chemical treatment for a substrate by using a processingliquid having a chemical activity varied depending on a temperature (aprocessing liquid having a reaction rate increased with a rise intemperature).

According to an aspect of the present invention, the substrateprocessing device includes a substrate holding portion for holding asubstrate in a substantially horizontal posture; a rotating portion forrotating the substrate held in the substrate holding portion in asubstantially horizontal plane; a heating portion for injecting heatingsteam to a peripheral edge part of the substrate to heat the peripheraledge part; a peripheral edge processing portion for supplying aprocessing liquid from above to the peripheral edge part heated by theheating portion, thereby carrying out a chemical treatment for theperipheral edge part; and a gas injecting portion for injecting a gasfrom above the substrate toward a predetermined injection target regiondefined within a range surrounded by a rotating track of the peripheraledge part of the substrate in an upper surface of the substrate, togenerate, on the substrate, a gas flow which flows from the injectiontarget region toward the peripheral edge part of the substrate.

The processing liquid is supplied to the peripheral edge part of thesubstrate heated by injecting the heating steam so that the chemicaltreatment for the peripheral edge part is carried out. Accordingly, itis possible to suppress reduction in a temperature of the peripheraledge part of the substrate by the rotation. Consequently, a change inthe chemical activity of the processing liquid is also reduced and anamount of consumption of the processing liquid and a time required forprocessing are suppressed. The gas is injected from above the substratetoward the predetermined injection target region defined within therange surrounded by the rotating track of the peripheral edge part ofthe substrate in the upper surface of the substrate, to generate, on thesubstrate, a gas flow which flows from the injection target regiontoward the peripheral edge part of the substrate. Consequently, it ispossible to prevent mist obtained by condensation of the steam or amist-like processing liquid from adhering onto a non-processed region ofthe upper surface of the substrate. Therefore, it is possible to supplya sufficient amount of steam for heating the peripheral edge part of thesubstrate while suppressing deterioration in the non-processed regiondue to the adhering of the mist.

Preferably, the substrate processing device further includes a lowersurface processing portion for supplying a processing liquid to a lowersurface of the substrate, thereby carrying out a chemical treatment forthe lower surface, the lower surface processing portion including anopposed surface which is opposed to a substantially entire region of thelower surface of the substrate which is rotated by the rotating portionand a processing liquid discharging port formed on the opposed surface,and discharging the processing liquid from the processing liquiddischarging portion to bring a space between the lower surface of thesubstrate and the opposed surface to a fluid-tight condition with theprocessing liquid.

The processing liquid is discharged from the processing liquiddischarging port of the lower surface processing portion including theopposed surface which is opposed to the substantially entire region ofthe lower surface of the substrate to be rotated so that the spacebetween the lower surface of the substrate and the opposed surface isbrought to the fluid-tight condition with the processing liquid.Therefore, even if the substrate is rotated at a low speed, theprocessing liquid can be supplied to the entire region of the lowersurface of the substrate. Consequently, it is possible to carry out thechemical treatment for the peripheral edge part and the lower surface inthe substrate while suppressing a drop in the temperature of theperipheral edge part of the substrate, thereby reducing energy requiredfor heating the peripheral edge part. Moreover, it is possible tosuppress wraparound of the processing liquid from the lower surface ofthe substrate to the peripheral edge part of the upper surface of thesubstrate by reducing the rotating speed of the substrate. Thus, it iseasy to control the processing width of the peripheral edge part.

According to another aspect of the present invention, the substrateprocessing device includes a substrate holding portion for holding asubstrate in a substantially horizontal posture; a rotating portion forrotating the substrate held in the substrate holding portion in asubstantially horizontal plane; a plurality of heating portions disposedto be opposed to a plurality of different positions in a rotating trackof a peripheral edge part of the substrate respectively and heating theperipheral edge part in the positions respectively; and a peripheraledge processing portion for supplying the processing liquid from aboveto the peripheral edge part heated by the plurality of heating portions,thereby carrying out a chemical treatment for the peripheral edge part.

The peripheral edge part is heated in the plurality of differentpositions in the rotating track of the peripheral edge part of thesubstrate respectively and the processing liquid is supplied to theperipheral edge part from above. Therefore, even in the case where theheating width in the radial direction in the peripheral edge part issmall, the temperature of the peripheral edge part can be prevented frombeing reduced. Even if the amount of the processing liquid is small, itis possible to enhance reactivity of the processing liquid bysuppressing reduction in a reaction rate of the processing liquid in theregion having a small width which is heated by the heating portion inthe peripheral edge part of the upper surface of the substrate.Accordingly, it is possible to reduce the chemical treating width whilesuppressing deterioration in each of uniformity of the chemicalprocessing width and processing efficiency.

The present invention is also directed to a substrate processing methodfor carrying out a chemical treatment for a substrate by using aprocessing liquid having a chemical activity varied depending on atemperature (a processing liquid having a reaction rate increased with arise in temperature).

According to an aspect of the present invention, a substrate processingmethod includes a rotating step of holding a substrate in asubstantially horizontal posture to rotate the substrate in asubstantially horizontal plane; a heating step of injecting heatingsteam to a peripheral edge part of the substrate to heat the peripheraledge part in parallel with the rotating step; a peripheral edgeprocessing step of supplying a processing liquid from above to theperipheral edge part which is heated in the heating step, therebycarrying out a chemical treatment for the peripheral edge part; and agas injecting step of injecting a gas from above the substrate toward apredetermined injection target region defined within a range surroundedby a rotating track of the peripheral edge part of the substrate in anupper surface of the substrate, to generate, on the substrate, a gasflow which flows from the injection target region toward the peripheraledge part of the substrate in parallel with the heating step and theperipheral edge processing step.

According to another aspect of the present invention, the substrateprocessing method includes a rotating step of holding a substrate in asubstantially horizontal posture to rotate the substrate in asubstantially horizontal plane; a heating step of heating a peripheraledge part of the substrate in a plurality of different positions in arotating track of the peripheral edge part respectively in parallel withthe rotating step; and a peripheral edge processing step of supplying aprocessing liquid from above to the peripheral edge part which is heatedin the heating step, thereby carrying out a chemical treatment for theperipheral edge part.

Therefore, it is an object of the present invention to provide atechnique capable of suppressing an amount of consumption of aprocessing liquid and a time required for processing. Moreover, it isanother object of the present invention to provide a technique capableof reducing a chemical treating width (an etching width or the like)while suppressing deterioration in each of uniformity of the chemicaltreating width and chemical treating efficiency (an etching rate or thelike).

These and other objects, features, aspects and advantages of the presentinvention will become more apparent from the following detaileddescription of the present invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view schematically showing an example of a schematicstructure of a substrate processing device according to a firstpreferred embodiment;

FIG. 2 is a view showing an example of a sectional view of a substrate;

FIG. 3 is a view showing an example of the sectional view obtained afteretching for the substrate in FIG. 2;

FIG. 4 is a top view schematically showing an arrangement of a nozzleunit with respect to an upper surface of a substrate;

FIGS. 5 and 6 are side views each illustrating an example of a structureof the nozzle unit;

FIGS. 7 to 9 are views for explaining processing for a back surface of asubstrate through a lower nozzle;

FIG. 10 is a flow chart showing an example of a flow of substrateprocessing according to a first preferred embodiment;

FIG. 11 is a view schematically showing an example of a schematicstructure of a substrate processing device according to a secondpreferred embodiment;

FIG. 12 is a top view schematically showing an arrangement of a nozzleunit with respect to an upper surface of a substrate;

FIGS. 13 to 15 are side views each illustrating an example of astructure of the nozzle unit;

FIG. 16 is a view showing an example of a positional relationshipbetween an injection target region of steam and a peripheral edge partof the substrate;

FIG. 17 is a view showing a comparison technique;

FIG. 18 is a view illustrating, in a graph, a difference in temperaturedistribution over the substrate depending on presence or absence of aheating portion; and

FIG. 19 is a view showing an example of a difference in an etching widthover the substrate depending on the presence or absence of the heatingportion;

FIG. 20 is a view showing an example of a sectional view of thesubstrate;

FIG. 21 is a view showing an example of the sectional view obtainedafter etching for the substrate of FIG. 20;

FIG. 22 is a view showing a comparative technique; and

FIG. 23 is a flow chart illustrating an example of a flow of substrateprocessing according to the second preferred embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A preferred embodiment according to the present invention will bedescribed below with reference to the drawings. Portions having the samestructures and functions have the same reference numerals in thedrawings, and repetitive description will be omitted in the followingexplanation. Moreover, each of the drawings is shown schematically, andfor example, a size, a positional relationship and the like of anillustrated member in the drawing are not always shown accurately.

Referring to First Preferred Embodiment <1. Structure of SubstrateProcessing Device>

FIG. 1 is a view schematically showing an example of a schematicstructure of a substrate processing device 100 according to a firstpreferred embodiment. The substrate processing device 100 carries out achemical treatment for a substrate by using a processing liquid having achemical activity varied depending on a temperature. More specifically,the substrate processing device 100 performs etching over a peripheraledge part (also referred to as “an upper surface peripheral edge part”)S3 of a substrate W such as a semiconductor wafer in a front surface(also referred to as “an upper surface”) S1 of the substrate W by usingan etchant as a processing liquid for the chemical treatment, therebyremoving a thin film (an unnecessary object) formed on the upper surfaceperipheral edge part S3. The upper surface peripheral edge part S3 is aring-shaped region having a width of 1.0 to 3.0 mm from a peripheraledge of the substrate W in the upper surface S1 of the substrate W, forexample. Moreover, the substrate processing device 100 also removes athin film formed on a back surface (also referred to as “a lowersurface) S2 of the substrate W by the etching. A upper surface shape ofthe substrate W is substantially circular, and the upper surface S1 ofthe substrate W implies a device formation surface on which a devicepattern is to be formed.

FIG. 2 is a view showing an example of a sectional view of the substrateW. FIG. 3 is a view showing an example of a sectional view obtainedafter the upper surface peripheral edge part S3 of the substrate Willustrated in FIG. 2 is subjected to etching. As shown in FIG. 2, acentral layer 11 of the substrate W is constituted by silicon or thelike. An insulating ground layer 12 is formed on the central layer 11 bya thin film such as a silicon nitride film or a silicon oxide film. Aninsoluble upper layer 13 is formed on the ground layer 12 by a thin filmsuch as a TiN (titanium nitride) layer, an Al (aluminum) layer, or a W(tungsten) layer. As shown in FIG. 3, in the substrate W, the upperlayer 13 in a region having a width 21 at a peripheral edge side of theupper surface peripheral edge part S3 is removed by the etching, forexample. In the example of FIG. 3, the etching is also carried out overthe back surface S2 of the substrate W so that the upper layer 13 in theentire region of the back surface S2 is also removed. Moreover, asubstrate having only the ground layer 12 formed on the central layer 11may be employed as the substrate W, for example, and the ground layer 12in the upper surface peripheral edge part S3 of the substrate W may beremoved.

In addition to the etchant to be used in the etching, most of chemicaltreating solutions have a chemical activity decreased with reduction intemperature. In other words, most of chemical treating solutions conformto the general Arrhenius equation in which a reaction rate is increasedwith a rise in temperature. In other words, most of processing liquidsbelong to “a processing liquid having a chemical activity varieddepending on a temperature (a processing liquid having a reaction rateincreased with a rise in temperature)”.

As shown in FIG. 1, the substrate processing device 100 includes a spinchuck (“a substrate holding portion”) 111 for holding and rotating thesubstrate W in a substantially horizontal posture with the upper surfaceS1 facing upward. The spin chuck 111 has a cylindrical rotating supportshaft 113 coupled to a rotating axis of a chuck rotating mechanism (“arotating portion”) 154 including a motor, and is rotatable around arotating axis a1 (a vertical axis), that is, in a substantiallyhorizontal plane by a driving operation of the chuck rotating mechanism154.

A disk-shaped spin base 115 is integrally coupled to an upper end of therotating support shaft 113 by means of a fastening component such as ascrew. Accordingly, the chuck rotating mechanism 154 is operated inresponse to an operation command sent from a control portion 151 forcontrolling the entire device so that the spin base 115 is rotatedaround the rotating axis a1. Moreover, the control portion 151 controlsthe chuck rotating mechanism 154 to regulate a rotating speed. Thecontrol portion 151 is implemented through execution of a program storedin a memory by a CPU or the like, for example.

A plurality of chuck pins 117 for gripping the peripheral edge part ofthe substrate W is erected in the vicinity of the peripheral edge partof the spin base 115. It is sufficient that at least three chuck pins117 are provided in order to reliably hold the circular substrate W, andthe chuck pins 117 are disposed at an equal angle interval along theperipheral edge part of the spin base 115. Each of the chuck pins 117includes a substrate supporting portion for supporting the peripheraledge part of the substrate W from below and a substrate holding portionfor pressing an outer peripheral end face of the substrate W supportedon the substrate supporting portion to hold the substrate W. Each of thechuck pins 117 is configured to be switchable between a pressing statein which the substrate holding portion presses the outer peripheral endface of the substrate W and a releasing state in which the substrateholding portion is released from the outer peripheral end face of thesubstrate W.

The plurality of chuck pins 117 are brought into the releasing statewhen the substrate W is transferred to the spin base 115, and theplurality of chuck pins 117 are brought into the pressing state whenetching is carried out over the substrate W. By setting the pressingstate, the plurality of chuck pins 117 can grip the peripheral edge partof the substrate W, thereby holding the substrate W in a substantiallyhorizontal posture at a predetermined interval from the spin base 115.Consequently, the substrate W is supported with the upper surface(pattern formation surface) S1 facing upward and the back surface S2facing downward. The member for holding the substrate is not restrictedto the chuck pin but a vacuum chuck for sucking the back surface S2 tosupport the substrate W may be used.

The spin chuck 111 thus holding the substrate W is rotationally drivenby the chuck rotating mechanism 154 to rotate the substrate W at apredetermined rotating speed, and at the same time, a processing liquidis supplied to the upper surface peripheral edge part S3 of the uppersurface S1 and the back surface S2 in the substrate W through aprocessing liquid supply nozzle 126 and a lower nozzle 141 which will bedescribed below, respectively. Consequently, a predetermined chemicaltreatment (etching) is performed.

FIG. 4 is a top view schematically showing an arrangement of a nozzleunit 120 with respect to the upper surface S1 of the substrate W. Forconvenience of illustration, a size of the nozzle unit 120 or the likeis set to be larger than an actual size with respect to the substrate W.FIGS. 5 and 6 are side views each showing an example of a structure ofthe nozzle unit 120.

A nozzle rotating mechanism 155 including a motor is provided on theside of the substrate W held on the spin chuck 111 as shown in FIGS. 1and 4, and an operation of the nozzle rotating mechanism 155 iscontrolled by the control portion 151. A rigid tubular piping arm 180 isattached to the nozzle rotating mechanism 155 pivotably in asubstantially horizontal plane with the nozzle rotating mechanism 155set to be a rotating center.

One of ends of the piping arm 180 penetrates the nozzle rotatingmechanism 155 to reach a lower surface thereof, and the other end can bepositioned above the upper surface peripheral edge part S3 of thesubstrate W by swinging of the piping arm 180 by the nozzle rotatingmechanism 155. The nozzle unit 120 is attached to the other end. In thetransfer of the substrate W to the spin base 115 or the like, the pipingarm 180 is swung so that the nozzle unit 120 is moved backward from adelivery-in path for the substrate W. Moreover, a position (a processingposition) of the nozzle unit 120 in the execution of the etching,rinsing, or the like is adjusted so that a width of the upper surfaceperipheral edge part S3 to be heated, an etching width, and the like areregulated.

As shown in FIGS. 4 to 6, the nozzle unit 120 is configured to include asteam injecting portion (“a heating portion”) 121 having a steaminjection nozzle 125 and a processing liquid discharging portion (“aperipheral edge processing part”) 122 having the processing liquidsupply nozzle 126 and a rinsing liquid supply nozzle 127. Pipes 181 to183 are connected to the steam injection nozzle 125, the processingliquid supply nozzle 126 and the rinsing liquid supply nozzle 127,respectively. The pipes 181 to 183 are disposed to pass through an innerpart of the piping arm 180 via an inner part of the nozzle unit 120 andto extend below the lower surface of the nozzle rotating mechanism 155,respectively.

The pipe 181 is connected in communication with a pipe 385 from a steamsupply source 131 (FIG. 1) at an outside of the substrate processingdevice 100. A heater 139 and an on-off valve 175 are provided in themiddle part of the pipe 385 in the substrate processing device 100. Theheater 139 heats steam passing through an inner part of the pipe 385depending on control of the control portion 151. In the steam supplysource 131, pure water or the like is heated so that steam for heatingthe peripheral edge part of the substrate W is generated. The heatingsteam thus generated is supplied as superheated steam having atemperature higher than 100° C. by means of the heater 139, for example.

The superheated steam at 110° C. is supplied from the steam supplysource 131 to the heater 139, for example, and a temperature of thesuperheated steam obtained immediately after heating by the heater 139is preferably set to be 140° C. to 160° C. or the like, for example. Thesteam to be supplied to the upper surface peripheral edge part S3 iscooled in a path for the supply to the nozzle unit 120, and furthermore,heat is taken by the upper surface peripheral edge part S3 also in theheating for the upper surface peripheral edge part S3 and the steam isthus cooled. However, the superheated steam having the high temperaturecan be maintained to have a high temperature even after being injectedfrom the steam injection nozzle 125 and used for heating the uppersurface peripheral edge part S3. Consequently, it is possible to preventheating steam 51 from being changed into mist in the upper surfaceperipheral edge part S3. Therefore, the mist obtained by condensation ofthe steam 51 can be prevented from adhering to a non-processed region ofthe substrate W.

Moreover, if the superheated steam having a high temperature is used, itis possible to raise the temperature of the upper surface peripheraledge part S3 of the substrate W higher as compared with the case wheresaturated steam having a temperature of 100° C. or less is supplied tothe steam injecting portion 121, for example. Consequently, it ispossible to increase an etching rate more greatly. As shown in FIG. 5,the heating steam 51 is injected onto the upper surface peripheral edgepart S3 along an injection path in an obliquely downward direction froman inside of the substrate W to an outside thereof. Consequently, themist obtained by the condensation of the steam 51 can also be preventedfrom adhering to the non-processed region of the upper surface S1 due toreturn to the substrate W side.

The on-off valve 175 is on-off controlled by means of a valve controlmechanism 152 which is controlled by the control portion 151. The valvecontrol mechanism 152 opens the on-off valve 175 as necessary so thatthe heating steam 51 (FIG. 5) supplied from the steam supply source 131to the steam injecting portion 121 is injected from the steam injectionnozzle 125 of the steam injecting portion 121 to the upper surfaceperipheral edge part S3. In other words, the steam injecting portion 121injects the heating steam 51 to the peripheral edge part of thesubstrate W, thereby heating the peripheral edge part.

Moreover, the substrate processing device 100 is also provided with aprocessing liquid supply source 132 for supplying an etchant (aprocessing liquid) which is stored therein and a rinsing liquid supplysource 133 for supplying a rinsing liquid which is stored therein. Asthe etchant, there is applied an etchant corresponding to a type of athin film to be removed from the peripheral edge part of the substrateW. For example, when a metal film such as a thin copper film is to beremoved from the peripheral edge part of the substrate W, SC2 (ahydrochloric acid/hydrogen peroxide mixture), a mixture of hydrofluoricacid and a hydrogen peroxide solution, or nitric acid is used as theetchant. Moreover, when a polysilicon film, an amorphous silicon film,or a silicon oxide film is to be removed from the substrate W, a mixtureof fluoric acid and nitric acid is used as the etchant, for example.Furthermore, when an oxide film or a nitride film on the substrate W isto be removed, fluoric acids such as DHF (diluted fluoric acid) or 50%fluoric acid are used as the etchant, for example. A temperature of theetchant is previously regulated to be a suitable temperature for adesirable etching rate, for example.

Pure water, DIW (deionized water) or the like is employed for therinsing liquid to be supplied by the rinsing liquid supply source 133. Atemperature of the rinsing liquid may be an ordinary temperature or ahigher temperature in order to enhance efficiency of the rinsing, forexample.

The pipe 182 connected to the processing liquid supply nozzle 126 of theprocessing liquid discharging portion 122 is connected in communicationwith a pipe 383 provided out of the processing liquid supply source 132,and an on-off valve 173 is provided in a middle part of the pipe 383.The pipe 183 connected to the rinsing liquid supply nozzle 127 of theprocessing liquid discharging portion 122 is connected in communicationwith a pipe 384 provided out of the rinsing liquid supply source 133. Anon-off valve 174 is provided in a middle part of the pipe 384.

The on-off valves 173 and 174 are on-off controlled by means of a valvecontrol mechanism 152 which is controlled by the control portion 151,and the valve control mechanism 152 selectively opens the on-off valve173 and the on-off valve 174 as necessary. If the on-off valve 173 isopened, a processing liquid 52 (FIG. 5) supplied from the processingliquid supply source 132 is discharged from the processing liquid supplynozzle 126 of the processing liquid discharging portion 122 and is thussupplied to the upper surface peripheral edge part S3. In other words,the processing liquid discharging portion 122 supplies the processingliquid 52 from above to the peripheral edge part of the substrate Wwhich is heated by the steam injecting portion 121, thereby carrying outa chemical treatment (etching) for the peripheral edge part.

In addition, if the on-off valve 174 is opened, a rinsing liquid 53(FIG. 6) supplied from the rinsing liquid supply source 133 isdischarged from the rinsing liquid supply nozzle 127 of the processingliquid discharging portion 122 and is thus supplied to the upper surfaceperipheral edge part S3. Consequently, rinsing for the peripheral edgepart of the substrate W is carried out.

As described above, in the substrate processing device 100, theprocessing liquid 52 is supplied to the peripheral edge part (the uppersurface peripheral edge part S3) of the substrate W which is heated bythe injection of the heating steam 51 so that the chemical treatment(etching) for the peripheral edge part is carried out. Accordingly, itis possible to prevent the temperature of the peripheral edge part ofthe substrate W from being reduced by rotation. Therefore, a change (adegree of reduction) in a chemical activity of the processing liquid 52is also reduced so that an amount of consumption of the processingliquid 52 and a processing time which are required for the chemicaltreatment are suppressed.

As shown in FIG. 4, the steam 51 is injected from the steam injectingportion 121 to the upper surface peripheral edge part S3 in apredetermined position (a first position) of a rotating track of theupper surface peripheral edge part S3 of the substrate W. Then, theprocessing liquid 52 is supplied from the processing liquid dischargingportion 122 to the upper surface peripheral edge part S3 in anotherpredetermined position (a second position) placed behind thepredetermined position along the rotating track. Accordingly, theprocessing liquid 52 is supplied from the processing liquid dischargingportion 122 to a portion of the upper surface peripheral edge part S3heated by the steam injecting portion 121 immediately after the heating.Thereafter, etching for the portion is carried out. Thus, thetemperature of the upper surface peripheral edge part S3 heated by thesteam injecting portion 121 is prevented from being reduced, and at thesame time, the etching for the upper surface peripheral edge part S3 iscarried out. Therefore, the etching rate can be enhanced.

Returning to FIG. 1, a through hole connected to a through hole of therotating support shaft 113 is formed on a central part of the spin base115. A cylindrical portion 143 is inserted into these through holes. Asubstantially disk-shaped lower nozzle 141 (also referred to as “a lowersurface processing portion”) is fixed to an upper end of the cylindricalportion 143. A processing liquid discharging port 148 is formed on thelower nozzle 141. The processing liquid discharging port 148 has anopening on a central part of an upper surface (an opposed surface) 145and penetrates the lower nozzle 141. The processing liquid dischargingport 148 is connected in communication with a supply tube 147 to be athrough hole formed by an internal wall of the cylindrical portion 143.The lower nozzle 141 supplies the processing liquid to be fed via thesupply tube 147 from the processing liquid discharging port 148 to theback surface S2 of the substrate W, thereby carrying out the etching(the chemical treatment) for the back surface S2.

A diameter of the lower nozzle 141 is set to be smaller than a diameterof the rotating track of the chuck pin 117 in such a manner that thechuck pin 117 erected on the rotating spin base 115 does not interferewith the lower nozzle 141. The upper surface 145 of the lower nozzle 141is an opposed surface which is opposed to a substantially entire regionof the back surface S2 of the substrate W to be rotated by the chuckrotating mechanism 154. Moreover, the upper surface 145 of the lowernozzle 141 takes a shape of a funnel in which an opening portion of thesupply tube 147 has a greater interval from the back surface S2 of thesubstrate W than a portion opposed to the peripheral edge part of thesubstrate W.

The processing liquid is supplied from the processing liquid supplysource 132 through a pipe 386 to the supply tube 147 connected to theprocessing liquid discharging port 148 of the lower nozzle 141, and therinsing liquid is supplied thereto from the rinsing liquid supply source133 through a pipe 388. On-off valves 176 and 178 are provided in themiddle parts of the pipes 386 and 388, respectively. The on-off valves176 and 178 are on-off controlled by means of the valve controlmechanism 152. The valve control mechanism 152 selectively opens theon-off valve 176 and the on-off valve 178 so that the processing liquidand the rinsing liquid are selectively supplied to the supply tube 147and are selectively discharged from the processing liquid dischargingport 148 on the upper surface 145 of the lower nozzle 141 toward theback surface S2 of the substrate W.

FIGS. 7 to 9 are sectional views showing the spin chuck 111, the lowernozzle 141, and the like for explaining the processing for the backsurface S2 of the substrate W through the lower nozzle 141. Thesesectional views illustrate a portion in which the chuck pin 117 is noterected on the spin base 115. FIG. 7 shows a state in which a space 149(FIG. 1) between the back surface S2 of the substrate W and the uppersurface 145 of the lower nozzle 141 is set to a fluid-tight conditionwith the processing liquid 52, and FIG. 8 shows a state in which thespace 149 is set to the fluid-tight condition with the rinsing liquid53. Moreover, FIG. 9 shows a state in which neither the processingliquid 52 nor the rinsing liquid 53 is present in the space 149.

The upper surface 145 of the lower nozzle 141 is opposed to thesubstantially entire region of the back surface S2 of the substrate W tobe rotated by the chuck rotating mechanism 154. Therefore, as shown inFIG. 7, the processing liquid 52 discharged from the supply tube 147 tothe back surface S2 brings the space (“a gap portion”) 149 (see FIG. 1)between the back surface S2 of the substrate W and the upper surface 145into the fluid-tight condition. Consequently, even if the substrate W isrotated at a low speed, the processing liquid 52 is supplied to theentire region of the back surface S2 of the substrate W. Thus, thetemperature of the peripheral edge part of the substrate W can beprevented from being reduced. Accordingly, also in the case where theetching for each of the upper surface peripheral edge part S3 and theback surface S2 of the substrate W is carried out at the same time, itis possible to perform the etching (the chemical treatment) for theupper surface peripheral edge part S3 and the back surface S2 of thesubstrate W with a small amount of processing liquid 52 (FIGS. 5 and 7)while suppressing energy required for heating the peripheral edge partof the substrate W. Moreover, it is possible to suppress the rotatingspeed of the substrate W. Therefore, it is possible to inhibitwraparound of the processing liquid from the back surface S2 to theupper surface peripheral edge part S3 in the substrate W. Consequently,it is easy to control a chemical treating width (an etching width) ofthe upper surface peripheral edge part S3.

Moreover, also in the case where the rinsing liquid is discharged fromthe supply tube 147 as shown in FIG. 8, the space 149 is brought intothe fluid-tight condition with the rinsing liquid so that the rinsingfor the back surface S2 can be carried out in the same manner as in thecase where the processing liquid is discharged.

As shown in FIG. 1, the substrate processing device 100 also includes asuction mechanism 158 having a suction pump below the rotating supportshaft 113. An operation of the suction mechanism 158 is controlled bythe control portion 151. The supply tube 147 of the cylindrical portion143 and the suction mechanism 158 are connected to each other through apipe 389, and an on-off valve 179 performing an on-off operation to becontrolled by the valve control mechanism 152 is provided in the middlepart of the pipe 389. When the on-off valve 179 is opened, theprocessing liquid or the rinsing liquid present in the space 149 betweenthe back surface S2 and the upper surface 145 is sucked by the suctionmechanism 158 and collected as shown in FIG. 9.

Moreover, as shown in FIG. 1, a nitrogen gas is supplied through a pipe387 from a nitrogen gas supply source 134 at an outside of the substrateprocessing device 100 to the supply tube 147. An on-off valve 177 to beon-off controlled by the valve control mechanism 152 is provided in themiddle part of the pipe 387. When the control portion 151 opens theon-off valve 177 through the valve control mechanism 152, the nitrogengas is supplied to the back surface S2 of the substrate W which is beingrotated with the rinsing liquid collected by the suction mechanism 158.

Great centrifugal force acts on the rinsing liquid adhered to the backsurface S2 by the rotation of the substrate W so that the rinsing liquidis shaken off toward the periphery of the substrate W and a dryingtreatment for the back surface S2 is carried out. Moreover, the backsurface S2 is also promoted to be dried with the nitrogen gas suppliedto the back surface S2, and the rinsing liquid shaken off toward theperiphery of the substrate W is also inhibited from returning to thesubstrate W side. The upper surface 145 of the lower nozzle 141 takesthe shape of the funnel described above. Therefore, it is easy tocollect the processing liquid or the rinsing liquid supplied to the backsurface S2 of the substrate W. Thus, the rinsing liquid is promoted tobe dried over the back surface S2.

In addition, a gas injection head (“a gas injecting portion”) 200 isprovided above a substantially central part of the substrate W. A gassupply path 282 penetrating a central part of the gas injection head 200in a vertical direction is formed in the gas injection head 200, and abuffer space BF is foamed in the gas injection head 200. A gas supplypath 283 is formed on a side of the gas supply path 282. The gas supplypath 283 has an opening on an upper surface side of the gas injectionhead 200 and is caused to communicate with the buffer space BF.Furthermore, a gas injection port communicating with the buffer space BFis provided in an outer peripheral part of a lower surface of the gasinjection head 200. The openings on the upper parts of the gas supplypaths 282 and 283 are connected to the nitrogen gas supply source 134 bymeans of pipes 381 and 382 through which on-off valves 171 and 172 areinserted, respectively.

The on-off valves 171 and 172 are on-off controlled by the valve controlmechanism 152 which is controlled by the control portion 151, and areopened as necessary so that the nitrogen gas is supplied from thenitrogen gas supply source 134 to the gas supply paths 282 and 283 inthe gas injection head 200, respectively. The nitrogen gas supplied tothe gas supply path 282 is injected as a nitrogen gas G1 (a gas forpurge) from the opening of the gas supply path 282 provided on the lowersurface side of the gas injection head 200 to the upper surface S1 ofthe substrate W.

In more detail, the nitrogen gas G1 is injected from the gas supply path282 provided above the substrate W toward a predetermined injectiontarget region defined within a range surrounded by the rotating track ofthe upper surface peripheral edge part S3 in the upper surface S1 of thesubstrate W. Then, the nitrogen gas G1 injected to the upper surface S1forms a gas flow which flows from the injection target region toward theupper surface peripheral edge part S3 of the substrate W. With the gasflow formed by the nitrogen gas G1, the mist obtained by thecondensation of the steam 51 injected from the steam injecting portion121 to the upper surface peripheral edge part S3, the processing liquid52 discharged from the processing liquid supply nozzle 126 of theprocessing liquid discharging portion 122 or the like can be preventedfrom adhering onto a non-processed region in which the etching is notcarried out in the upper surface S1 of the substrate W. Accordingly, itis possible to supply a sufficient amount of steam for heating theperipheral edge part of the substrate W while suppressing deteriorationin the non-processed region due to the adhering of the mist.

Moreover, also in a drying treatment for the upper surface S1 of thesubstrate W after the end of the rinsing, the substrate W is promoted tobe dried with the nitrogen gas G1 supplied from the gas supply path 282,and furthermore, the rinsing liquid shaken off from the upper surfaceperipheral edge part S3 toward the outside of the substrate W by thecentrifugal force acting through the rotation of the substrate W canalso be prevented from returning to the substrate W and adhering ontothe non-processed region of the upper surface S1.

The nitrogen gas supplied to the gas supply path 283 is injected as anitrogen gas G2 (a gas for curtain) from a gas injection port foamed onthe outer peripheral part of the lower surface of the gas injection head200 to the upper surface S1 via the buffer space BF. Consequently, thenitrogen gas G1 injected to the upper surface S1 of the substrate W issupplied toward the upper surface peripheral edge part S3 along theupper surface S1 of the substrate W. Therefore, it is possible toefficiently prevent the non-processed region from being deteriorated bythe adhering of the mist or the like.

The gas injection head 200 is held above the spin base 115 by means ofan arm (not shown), while the arm is configured to be upward anddownward movable in connection with a head up-down mechanism 153 to becontrolled by the control portion 151. With this structure, when theetching for the substrate W or the like is to be carried out, the gasinjection head 200 is positioned at a predetermined interval (forexample, approximately 2 to 10 mm) opposite to the upper surface S1 ofthe substrate W held in the spin chuck 111. Moreover, when the substrateW is transferred to the spin chuck 111 or is received from the spinchuck 111, the gas injection head 200 is moved upward from the spinchuck 111.

<2. Operation of Substrate Processing Device>

FIG. 10 is a flow chart showing an example of a flow of substrateprocessing to be carried out by the substrate processing device 100according to the first preferred embodiment. Before the start of theprocessing, each of the on-off valves is closed and the spin chuck 111is stationary. Moreover, the gas injection head 200 is moved backward toa predetermined separating position and the nozzle unit 120 is placed ina standby position other than a delivery-in path for the substrate W.First of all, a single substrate W is delivered by a substrate deliveryrobot (not shown) into a processing chamber (chamber) (not shown) inwhich the spin chuck 111 is disposed, and is mounted on the spin chuck111 to be held by the chuck pin 117 (step S110).

Subsequently, the gas injection head 200 is moved downward to aprocessing position placed above the upper surface S1 of the substrate Wat a predetermined interval (for example, approximately 2 to 10 mm) bymeans of the head up-down mechanism 153. Then, the on-off valves 171 and172 are opened sand the gas injection head 200 injects the nitrogen gassupplied from the nitrogen gas supply source 134 as the nitrogen gas G1(the gas for purge) and the nitrogen gas G2 (the gas for curtain) ontothe upper surface S1 of the substrate W (step S120).

Next, the nozzle unit 120 is positioned above the upper surfaceperipheral edge part S3 of the substrate W and the control portion 151controls the chuck rotating mechanism 154 so that the rotation of thespin chuck 111 is started at a predetermined rotating speed of 50 rpm to1000 rpm, for example (step S130). Then, the on-off valve 175 is openedso that the heating steam generated by the steam supply source 131 andheated by the heater 139 is supplied to the nozzle unit 120. The nozzleunit 120 starts the injection of the heating steam from the steaminjection nozzle 125 toward the upper surface peripheral edge part S3(step S140), thereby starting to heat the upper surface peripheral edgepart S3.

Subsequently, the etching for the upper surface peripheral edge part S3and the back surface S2 of the substrate W is carried out (step S150).More specifically, the on-off valve 173 is opened, and the processingliquid is supplied from the processing liquid supply source 132 to thenozzle unit 120 and discharged from the processing liquid supply nozzle126 to the upper surface peripheral edge part S3 which is heated. Then,the etching for the upper surface peripheral edge part S3 of thesubstrate W is carried out with the discharged processing liquid.

Moreover, in parallel with the etching for the upper surface peripheraledge part S3, the on-off valve 176 is opened so that the processingliquid supplied from the processing liquid supply source 132 isdischarged from the processing liquid discharging port of the lowernozzle 141 toward the back surface S2 of the substrate W via the supplytube 147 of the cylindrical portion 143. Consequently, as shown in FIG.7, the space 149 between the back surface S2 of the substrate W and thelower nozzle 141 is brought into a fluid-tight condition with theprocessing liquid 52, and the etching for the back surface S2 is carriedout.

When a predetermined time elapsed and the etching for the upper surfaceperipheral edge part S3 and the back surface S2 is completed, the on-offvalve 175 and the on-off valve 176 are closed so that the supply of theprocessing liquid to the substrate W is stopped. Then, the on-off valve175 is closed so that the injection of the heating steam is stopped(step S160). Subsequently, the on-off valve 179 is opened so that thesuction mechanism 158 is driven, and the processing liquid accumulatedin the space 149 between the back surface S2 of the substrate W and theupper surface 145 of the lower nozzle 141 is sucked and collected. Whenthe collection of the processing liquid is completed, the on-off valve179 is closed so that the suction mechanism 158 is stopped.

Next, the rinsing for the upper surface peripheral edge part S3 and theback surface S2 of the substrate W is carried out (step S170). Morespecifically, the on-off valves 174 and 178 are opened and the supply ofthe rinsing liquid from the rinsing liquid supply source 133 is started.Thereafter, the rinsing liquid is discharged from the rinsing liquidsupply nozzle 127 of the nozzle unit 120 to the upper surface peripheraledge part S3 to carry out the rinsing for the upper surface peripheraledge part S3, and furthermore, the rinsing liquid is supplied from theprocessing liquid discharging port of the lower nozzle 141 to the backsurface S2.

The space 149 between the substrate W and the lower nozzle 141 isbrought into the fluid-tight condition with the rinsing liquid 53supplied from the lower nozzle 141 as shown in FIG. 8. Thus, the rinsingfor the back surface S2 of the substrate W is carried out. When apredetermined time elapsed and the rinsing for the upper surfaceperipheral edge part S3 and the back surface S2 is completed, the on-offvalves 174 and 178 are closed so that the supply of the rinsing liquidis stopped. Thereafter, the on-off valve 179 is opened so that thesuction mechanism 158 is driven and the rinsing liquid accumulated inthe space 149 between the substrate W and the lower nozzle 141 is suckedand collected. When the collection of the rinsing liquid is completed,the on-off valve 179 is closed so that the suction mechanism 158 isstopped.

Subsequently, the rotating speed of the spin chuck 111 is raised to behigh, that is, 1000 to 1500 rpm, for example, in such a manner that thecentrifugal force acting on the rinsing liquid remaining in the uppersurface peripheral edge part S3 and the back surface S2 is increased.Consequently, the remaining rinsing liquid is shaken off to the outsideof the substrate W so that a drying treatment (spin drying) for theupper surface S1 and the back surface S2 of the substrate W is carriedout (step S180). In the spin drying, the on-off valve 177 is opened andthe nitrogen gas supplied from the nitrogen gas supply source 134 isinjected from the processing liquid discharging port of the lower nozzle141 to the back surface S2 of the substrate W, while the supply of thenitrogen gases G1 and G2 from the gas injection head 200 to the uppersurface peripheral edge part S3 is continuously carried out.Consequently, the rinsing liquid adhered onto the upper surfaceperipheral edge part S3 and the back surface S2 can be promoted to bedried, and furthermore, the shaken-off rinsing liquid can be preventedfrom returning to the substrate W side and adhering onto thenon-processed region of the upper surface S1.

When a predetermined time elapsed since the start of the dryingtreatment, the rotation of the spin chuck 111 is stopped so that thedrying treatment is ended (step S190). Subsequently, the on-off valves171 and 172 are closed so that the injection of the nitrogen gas G1 (thegas for purge) and the nitrogen gas G2 (the gas for curtain) from thegas injection head 200 is stopped (step S200).

When the injection of the gas from the gas injection head 200 isstopped, the control portion 151 controls the head up-down mechanism 153to lift the gas injection head 200 to a predetermined separatingposition, and controls the nozzle rotating mechanism 155 to move thenozzle unit 120 to a standby position. Then, the processed substrate Wis removed from the spin chuck 111 and is delivered to the outside ofthe processing chamber by means of a delivery robot (not shown) (stepS210), and the substrate processing carried out by the substrateprocessing device 100 is ended.

According to the substrate processing device in accordance with thefirst preferred embodiment configured as described above, the processingliquid is supplied to the upper surface peripheral edge part S3 of thesubstrate W heated by the injection of the heating steam so that thechemical treatment (the etching) for the upper surface peripheral edgepart S3 is carried out. Therefore, the temperature of the peripheraledge part of the substrate W can be prevented from being reduced by therotation. Consequently, a change in a chemical activity (a degree ofreduction) of the processing liquid is also reduced so that an amount ofconsumption of the processing liquid and a time required for theprocessing are suppressed. Moreover, the substrate processing deviceinjects the gas (the nitrogen gas G1) from above the substrate W towarda predetermined injection target region defined within a rangesurrounded by the rotating track of the upper surface peripheral edgepart S3 of the substrate W in the upper surface S1 of the substrate W,thereby generating, on the substrate W, a gas flow which flows from theinjection target region toward the upper surface peripheral edge part S3of the substrate W. Consequently, the mist obtained by the condensationof the steam or the mist-like processing liquid can be prevented fromadhering onto the non-processed region in the upper surface S1 of thesubstrate W. Accordingly, it is possible to supply a sufficient amountof steam for heating the peripheral edge part of the substrate W whileinhibiting the non-processed region from being deteriorated by theadhering of the mist.

Moreover, according to the substrate processing device in accordancewith the first preferred embodiment configured as described above, theprocessing liquid is discharged from the processing liquid dischargingport of the lower nozzle 141 having the upper surface 145 (the opposedsurface) which is opposed to the substantially entire region of the backsurface S2 of the rotated substrate W, and the space 149 between theback surface S2 of the substrate W and the opposed surface is thusbrought into the fluid-tight condition with the processing liquid. Forthis reason, even if the substrate W is rotated at a low speed, theprocessing liquid can be supplied to the entire region of the backsurface S2 of the substrate W. Consequently, it is possible to carry outthe chemical treatment (the etching) for the upper surface peripheraledge part S3 and the back surface S2 of the substrate W while inhibitingreduction in the temperature of the peripheral edge part of thesubstrate W to suppress energy required for heating the peripheral edgepart. Moreover, it is possible to prevent the wraparound of theprocessing liquid from the back surface S2 of the substrate W to theupper surface peripheral edge part S3 in the upper surface S1 bysuppressing the rotating speed of the substrate W. Thus, it is easy tocontrol the processing width of the upper surface peripheral edge partS3.

Moreover, according to the substrate processing device in accordancewith the first preferred embodiment configured as described above, theupper surface 145 (the opposed surface) of the lower nozzle 141 takes ashape of a funnel in which the processing liquid discharging port 148portion of the lower nozzle 141 has a greater interval from the backsurface S2 of the substrate W than the portion opposed to the peripheraledge part of the substrate W. Accordingly, it is easy to collect theprocessing liquid or the rinsing liquid which is supplied to the backsurface S2 of the substrate W. Therefore, during the drying treatmentfor the back surface S2, the rinsing liquid adhered onto the backsurface S2 and remaining thereon is promoted to be dried.

Furthermore, according to the substrate processing device in accordancewith the first preferred embodiment configured as described above, thesteam injecting portion 121 and the processing liquid dischargingportion 122 are provided in a positional relationship in which theheating steam is injected from the steam injecting portion 121 to theupper surface peripheral edge part S3 in a first position of therotating track of the upper surface peripheral edge part S3 of thesubstrate W and the processing liquid is supplied from the processingliquid discharging portion 122 to the upper surface peripheral edge partS3 in a second position placed behind the first position along therotating track. Accordingly, the processing liquid 52 is supplied fromthe processing liquid discharging portion 122 to the upper surfaceperipheral edge part S3 portion heated by the steam injecting portion121 immediately after the heating. Then, the etching for the portion iscarried out. The etching is carried out for each of the portions of theupper surface peripheral edge part S3 heated by the steam injectingportion 121 while the temperature is prevented from being reduced.Therefore, the etching rate can be enhanced.

In the substrate processing device 100, for example, the nitrogen gassupply source 134 and the steam supply source 131 may be provided in thesubstrate processing device 100. Moreover, it is also possible to employa structure in which a dry gas such as dry air or an inert gas otherthan the nitrogen gas is supplied in place of the supply of the nitrogengas through the nitrogen gas supply source 134. Furthermore, since aheating mechanism is provided to heat the inert gas, it is also possibleto further prevent the reduction in the temperature, thereby promotingthe rinsing liquid to be dried. Moreover, although the respectivenozzles or the like in the nozzle unit 120 are integrally moved with thesubstrate W, they may be individually movable, respectively. Inaddition, the etching for the upper surface peripheral edge part S3 ofthe substrate W and the etching for the back surface S2 may besequentially carried out. Furthermore, among the nozzle unit 120 and thelower nozzle 141, even if the substrate processing device 100 includesonly the nozzle unit 120 and carries out only the etching for the uppersurface peripheral edge part S3 among the etching for the upper surfaceperipheral edge part S3 and the etching for the back surface S2, theusefulness of the present invention is not lost. Furthermore, in placeof the gas injection head 200, a blocking plate may be employed tosupply the nitrogen gas from the blocking plate to the upper surface S1of the substrate W. Moreover, in the explanation of the flow of thesubstrate processing carried out by the substrate processing device 100with reference to FIG. 10, the nozzle unit 120 is positioned above theupper surface peripheral edge part S3 of the substrate W and therotation of the spin chuck 111 is started, and the nozzle unit 120 thenstarts the injection of the heating steam. However, for example, thespin chuck 111 may start the rotation and the nozzle unit 120 may thenstart the injection of the heating steam, and thereafter, the nozzleunit 120 may be positioned above the upper surface peripheral edge partS3 of the substrate W.

Referring to Second Preferred Embodiment <3. Structure of SubstrateProcessing Device>

FIG. 11 is a view schematically showing an example of a schematicstructure of a substrate processing device 600 according to a secondpreferred embodiment. The substrate processing device 600 carries out achemical treatment for a substrate by using a processing liquid having areaction rate increased with a rise in temperature. More specifically,the substrate processing device 600 performs etching for a peripheraledge part (also referred to as “a upper surface peripheral edge part”)S3 of a substrate W6 such as a semiconductor wafer in a front surface(also referred to as “an upper surface”) S1 of the substrate W6 by usingan etchant as a processing liquid for the chemical treatment, therebyremoving a thin film (an unnecessary object) formed on a upper surfaceperipheral edge part S8. The upper surface peripheral edge part S8 is aring-shaped region having a width of 0.5 to 3.0 mm from a peripheraledge of the substrate W6 in the upper surface S6 of the substrate W6,for example. A back surface S7 at a side opposite to the upper surfaceS6 will also be referred to as “a lower surface”. A surface shape of thesubstrate W6 is substantially circular, and the upper surface S6 of thesubstrate W6 implies a device formation surface on which a devicepattern is to be formed.

As described above, in addition to the etchant to be used in theetching, most of chemical processing liquids conform to the generalArrhenius equation in which a reaction rate is increased with a rise intemperature. In other words, most of processing liquids belong to “aprocessing liquid having a reaction rate increased with a rise intemperature”.

FIG. 20 is a view showing an example of a sectional view of thesubstrate W6. As shown in FIG. 20, a central layer 16 of the substrateW6 is constituted by silicon (Si). An insulating film which does notconduct electricity, for example, a thermal oxide film (Th—SiO₂), Hf(hafnium), Hf oxide, or the like is formed as a lower film (alsoreferred to as “a ground layer”) 17 over the central layer 16. Then,over the lower film 17, a barrier metal film such as a TiN film or a TaNfilm or a metal film such as an Al film, a W film, a NiSi film, or a Cufilm is formed as an upper film (also referred to as “an upper layer”)18. In the substrate W6, the upper film 18 in a region (a processedregion) at a peripheral edge side in the upper surface peripheral edgepart S8 is removed by etching. For example, a substrate having only thelower film 17 formed on the central layer 16 may be employed as thesubstrate W6, and the lower film 17 in the processed region of the uppersurface peripheral edge part may be removed.

As shown in FIG. 11, the substrate processing device 600 includes a spinchuck (“a substrate holding portion”) 611 for holding and rotating thesubstrate W6 in a substantially horizontal posture with the uppersurface S6 facing upward. The spin chuck 611 has a cylindrical rotatingsupport shaft 613 coupled to a rotating axis of a chuck rotatingmechanism (“a rotating portion”) 654 including a motor, and is rotatablearound a rotating axis a6 (a vertical axis), that is, in a substantiallyhorizontal plane by a driving operation of the chuck rotating mechanism654.

A disk-shaped spin base 615 is integrally coupled to an upper end of therotating support shaft 613 by means of a fastening component such as ascrew. Accordingly, the chuck rotating mechanism 654 is operated inresponse to an operation command sent from a control portion 651 forcontrolling the entire device so that the spin base 615 is rotatedaround the rotating axis a6. Moreover, the control portion 651 controlsthe chuck rotating mechanism 654 to regulate a rotating speed. Thecontrol portion 651 is implemented through execution of a program storedin a memory by a CPU or the like, for example.

A plurality of chuck pins 617 for gripping the peripheral edge part ofthe substrate W6 is erected in the vicinity of the peripheral edge partof the spin base 615. It is sufficient that at least three chuck pins617 are provided in order to reliably hold the circular substrate W6,and the chuck pins 617 are disposed at an equal angle interval along theperipheral edge part of the spin base 615. Each of the chuck pins 617includes a substrate supporting portion for supporting the peripheraledge part of the substrate W6 from below and a substrate holding portionfor pressing an outer peripheral end face of the substrate W6 supportedon the substrate supporting portion to hold the substrate W6. Each ofthe chuck pins 617 is configured to be switchable between a pressingstate in which the substrate holding portion presses the outerperipheral end face of the substrate W6 and a releasing state in whichthe substrate holding portion is released from the outer peripheral endface of the substrate W6.

The plurality of chuck pins 617 are brought into the releasing statewhen the substrate W6 is transferred to the spin base 615, and theplurality of chuck pins 617 are brought into the pressing state whenetching is carried out over the substrate W6. By setting the pressingstate, the chuck pins 617 can grip the peripheral edge part of thesubstrate W6 to hold the substrate W6 in a substantially horizontalposture at a predetermined interval from the spin base 615.Consequently, the substrate W6 is supported with the upper surface(pattern formation surface) S1 facing upward and the back surface S7facing downward. As a member for holding the substrate W6, it is alsopossible to use a vacuum chuck which sucks the back surface S7 tosupport the substrate W6, in addition to a member using a chuck pin.

The spin chuck 611 thus holding the substrate W6 is rotationally drivenby the chuck rotating mechanism 654 to rotate the substrate W6 at apredetermined rotating speed, and at the same time, a processing liquidis supplied to the upper surface peripheral edge part S8 of the uppersurface S6 of the substrate W6 through a processing liquid supply nozzle626 which will be described below. Consequently, a predeterminedchemical treatment (etching) is performed.

FIG. 12 is a top view schematically showing the arrangement of a nozzleunit 620 (660) with respect to the upper surface S6 of the substrate W6.For convenience of illustration, a size of the nozzle unit 620 (660) isillustrated to be larger than an actual size with respect to thesubstrate W6. FIGS. 13 and 14 are side views showing an example of astructure of the nozzle unit 620. FIG. 15 is a side view showing anexample of a structure of the nozzle unit 660.

As shown in FIGS. 11 and 12, nozzle rotating mechanisms 655 and 656including motors are provided on the side of the substrate W6 held onthe spin chuck 611, and operations of the nozzle rotating mechanisms 655and 656 are controlled by the control portion 651. A rigid tubularpiping arm 680 (690) is pivotably attached to the nozzle rotatingmechanism 655 (656) in a substantially horizontal plane with the nozzlerotating mechanism 655 (656) set to be a rotating center.

One of ends of the piping arm 680 (690) penetrates the nozzle rotatingmechanism 655 (656) to reach a lower surface thereof, and the other endcan be positioned above the upper surface peripheral edge part S8 of thesubstrate W6 by swinging of the piping arm 680 (690) through the nozzlerotating mechanism 655 (656). The nozzle unit 620 (660) is attached tothe other end. Upon the transfer of the substrate W6 to the spin base615 or the like, the piping arm 680 (690) is swung so that the nozzleunit 620 (660) is moved backward from a delivery-in path for thesubstrate W6. Moreover, a position (a processing position) of the nozzleunit 620 (660) upon execution of etching, rinsing, or the like isaccurately adjusted by servo control so that a width of the uppersurface peripheral edge part S8 to be heated, an etching width, or thelike is regulated.

As shown in FIGS. 12 to 14, the nozzle unit 620 is configured to includea heating portion 621 having a steam injection nozzle 625, a processingliquid discharging portion (“a peripheral edge processing portion”) 622having a processing liquid supply nozzle 626 and a rinsing liquid supplynozzle 627, and a nitrogen gas injecting portion 624 having a nitrogengas injection nozzle 628. Pipes 681 to 684 are connected to the steaminjection nozzle 625, the processing liquid supply nozzle 626, therinsing liquid supply nozzle 627, and the nitrogen gas injection nozzle628, respectively. The pipes 681 to 684 are disposed to pass through aninner part of the piping arm 680 via an inner part of the nozzle unit620 and to extend below the lower surface of the nozzle rotatingmechanism 655, respectively.

Moreover, as shown in FIG. 15, the nozzle unit 660 is configured toinclude a heating portion 661 having a steam injection nozzle 665 and anitrogen gas injecting portion 664 having a nitrogen gas injectionnozzle 668. Pipes 691 and 694 are connected to the steam injectionnozzle 665 and the nitrogen gas injection nozzle 668, respectively. Thepipes 691 and 694 are disposed to pass through an inner part of thepiping arm 690 via an inner part of the nozzle unit 660 and to extendbelow the lower surface of the nozzle rotating mechanism 656,respectively. As shown in FIGS. 12 to 15, the heating portions 621 and661 are disposed to be opposed to two different positions from eachother in the rotating track of the peripheral edge part of the substrateW6, respectively.

As shown in FIG. 11, a steam supply source 631 provided on the outsideof the substrate processing device 600 is connected in communicationwith a pipe 885. A heater 639 and an on-off valve 675 are provided inthe middle part of the pipe 885 in the substrate processing device 600.The pipe 885 branches into two parts at a downstream side (the spinchuck 611 side) of the on-off valve 675. One of the branching pipes 885is connected in communication with the pipe 681 (FIG. 13) and the otheris connected in communication with the pipe 691 (FIG. 15).

The heater 639 heats steam passing through the inside of the pipe 885depending on the control of the control portion 651. In the steam supplysource 631, pure water or the like is heated so that steam for heatingthe peripheral edge part of the substrate W6 is generated. The heatingsteam thus generated is supplied as superheated steam having atemperature higher than 100° C. by the heater 639, for example.

The superheated steam at 110° C. is supplied from the steam supplysource 631 to the heater 639, for example, and a temperature of thesuperheated steam obtained immediately after heating by the heater 639is preferably set to be 140° C. to 160° C. or the like, for example. Thesteam to be supplied to the upper surface peripheral edge part S8 iscooled in a path for the supply to the nozzle unit 620 (660), andfurthermore, is cooled by taking heat through the upper surfaceperipheral edge part S8 also during the heating for the upper surfaceperipheral edge part S8. However, the superheated steam having a hightemperature is injected through the steam injection nozzle 625 (665) andcan also be maintained to have the high temperature also after it isused for heating the upper surface peripheral edge part S8. It ispossible to suppress a change of heating steam 56 (FIGS. 13 and 15) intomist in the upper surface peripheral edge part S8. Accordingly, the mistobtained by the condensation of the steam 56 can be prevented fromadhering onto the non-processed region of the substrate W6.

Moreover, if the superheated steam having the high temperature is used,the temperature of the upper surface peripheral edge part S8 of thesubstrate W6 can be raised more greatly as compared with the case wheresaturated steam having a temperature of 100° C. or less is supplied tothe heating portion 621 (661), for example. Thus, the etching rate canbe increased more greatly. As shown in FIG. 13 (FIG. 15), the heatingsteam 56 is injected through the steam injection nozzle 625 (665) to theupper surface peripheral edge part S8 along an injection path in anobliquely downward direction from an inside of the substrate W6 towardan outside thereof. Consequently, the mist obtained by the condensationof the steam 56 can be prevented from adhering onto the non-processedregion of the upper surface S6 due to return to the substrate W6 side.

The on-off valve 675 is on-off controlled by a valve control mechanism652 which is controlled by means of the control portion 651. The valvecontrol mechanism 652 opens the on-off valve 675 as necessary so thatthe heating steam 56 supplied from the steam supply source 631 to theheating portion 621 (661) is injected from the steam injection nozzle625 (665) of the heating portion 621 (661) to the upper surfaceperipheral edge part S8. Then, the upper surface peripheral edge part S8is heated.

As described above, the substrate processing device 600 according to thesecond preferred embodiment includes the two heating portions 621 and661 which are disposed to be opposed to the two different positions fromeach other in the rotating track of the peripheral edge part of thesubstrate W6 respectively, and injects the heating steam from theseheating portions to the upper surface peripheral edge part S8 of thesubstrate W6, thereby heating the upper surface peripheral edge part S8.The substrate processing device 600 may include at least three heatingportions which are the same as these heating portions, thereby heatingthe upper surface peripheral edge part S8. In other words, the substrateprocessing device 600 includes a plurality of heating portions which isdisposed to be opposed to a plurality of different positions in therotating track of the peripheral edge part of the substrate W6respectively and serves to heat the peripheral edge part of thesubstrate W6 in the plurality of positions respectively.

For the heating steam, that is, a heating fluid, it is also possible toemploy a fluid other than steam which is made of a material having nochemical reactivity to a substance that is present in the peripheraledge part of the substrate. Moreover, the heating portion of thesubstrate processing device 600 may irradiate the upper surfaceperipheral edge part S8 with a laser beam or light emitted from a lampsuch as a halogen lamp, thereby heating the upper surface peripheraledge part S8. In other words, it is also possible to implement theplurality of heating portions of the substrate processing device 600 byincluding at least one of a thermal fluid supplying portion forsupplying the heated fluid to the peripheral edge part of the substrateW6 to heat the peripheral edge part and a light irradiating portion forirradiating the peripheral edge part of the substrate W6 with light toheat the peripheral edge part.

FIG. 16 is a view showing an example of a positional relationshipbetween injection target regions 76 a and 76 b of the steam to beinjected from the heating portions 621 and 661 respectively and theupper surface peripheral edge part S8 of the substrate W6. As shown inFIG. 16, the heating steam to be injected from each of the heatingportions 621 and 661 is injected to be partially applied to the uppersurface peripheral edge part S8, so that the upper surface peripheraledge part S8 is spatially exposed to a part of the heating steam. Awidth 36 is equivalent to a width in a radial direction of the substrateW6 in which the upper surface peripheral edge part S8 is exposed to theheating steam. Similarly, also in the case where heating light isemitted from the heating portion in place of the heated fluid, the uppersurface peripheral edge part S8 of the substrate W6 is spatially exposedto a part of the heating light.

In other words, the heating portions 621 and 661 of the substrateprocessing device 600 are implemented to include at least one of athermal fluid supplying portion for injecting a thermal medium such asthe heating steam to partially expose the peripheral edge part of thesubstrate W6 to a part of a section of a flux of the thermal medium,thereby heating the peripheral edge part and a light irradiating portionfor emitting light to partially expose the peripheral edge parts of thesubstrate W6 to a part of a section of a bundle of rays for the light,thereby heating the peripheral edge parts respectively.

For example, as in the injection target regions 77 a and 77 b shown inFIG. 17, in the case where the upper surface peripheral edge part S8 isexposed to the entire injected heating fluid or the like, a width 37 ina radial direction of the substrate in which the upper surfaceperipheral edge part S8 is exposed to the heating fluid or the like isgreater than a width in the case where the upper surface peripheral edgepart S8 is exposed to a part of the heating fluid or the like, forexample, the width 36 shown in FIG. 16, and the etching width is thusincreased.

In contrast, according to the substrate processing device 600, the uppersurface peripheral edge part S8 of the substrate W6 is spatially exposedto a part of the heated fluid to be injected from the plurality ofheating portions respectively (light to be irradiated). Consequently, itis possible to reduce the heating width of the upper surface peripheraledge part S8 more greatly while efficiently heating the upper surfaceperipheral edge part S8. In the case where an etchant (a processingliquid) having a reaction rate increased with a rise in temperature isused, it is possible to reduce an etching width (a chemical treatingwidth) by decreasing the heating width of the upper surface peripheraledge part S8. In the case where the heating steam is injected to theupper surface peripheral edge part S8, it is possible to decrease theetching width to approximately 0.5 mm to 1 mm, for example.

As compared with light emitted from a halogen lamp, the heating steamhas a larger amount of heat. Therefore, in the case where the heatingsteam is injected from the heating portions 621 and 661, it is possibleto heat the upper surface peripheral edge part S8 more efficiently ascompared with the case where the upper surface peripheral edge part S8is heated with light emitted from the halogen lamp or the like.Moreover, differently from the case where light is used, glass is notrequired in the heating portion. For this reason, continuous use for along period of time is possible even in the case where an HF solution isutilized as a processing liquid, for example.

Moreover, as shown in FIG. 11, the substrate processing device 600 isalso provided with a processing liquid supply source 632 for supplyingan etchant (a processing liquid) which is stored therein and a rinsingliquid supply source 633 for supplying a rinsing liquid which is storedtherein. For example, SC1 (ammonia-hydrogen peroxide mixture), SC2, HF(hydrofluoric acid), or the like is employed for the etchant. If a metalcomponent such as Mo or Co adheres onto a contact part with a wafer inanother manufacturing apparatus or a delivery system, an inside ofFOUP/FOSB holding a wafer, or the like, contamination is caused. Forthis reason, the SC2 is used for washing a bevel portion or a backsurface of the wafer in order to remove the adhered metal component, forexample. Thus, in some cases, the processing liquid stored in theprocessing liquid supply source 632 is supplied to the wafer for thepurpose other than etching.

Pure water (DIW: deionized water) or the like is employed for therinsing liquid to be supplied by the rinsing liquid supply source 633.Functional water or warm water may be employed for the rinsing liquid.

The pipe 682 connected to the processing liquid supply nozzle 626 of theprocessing liquid discharging portion 622 is connected in communicationwith a pipe 883 provided out of the processing liquid supply source 632,and an on-off valve 673 is provided in the middle part of the pipe 883.The pipe 683 connected to the rinsing liquid supply nozzle 627 of theprocessing liquid discharging portion 622 is connected in communicationwith a pipe 884 provided out of the rinsing liquid supply source 633. Anon-off valve 674 is provided in the middle part of the pipe 884.

The on-off valves 673 and 674 are on-off controlled by means of a valvecontrol mechanism 652 which is controlled by the control portion 651,and the valve control mechanism 652 selectively opens the on-off valve673 and the on-off valve 674 as necessary.

If the on-off valve 673 is opened, a processing liquid 57 (FIG. 13)supplied from the processing liquid supply source 632 is discharged fromthe processing liquid supply nozzle 626 of the processing liquiddischarging portion 622 and is then supplied to the upper surfaceperipheral edge part S8. In other words, the processing liquiddischarging portion 622 supplies the processing liquid 57 from above tothe peripheral edge part of the substrate W6 which is heated by theplurality of heating portions, thereby carrying out a chemical treatment(etching) for the peripheral edge part. A flow rate of the processingliquid to be supplied to the upper surface peripheral edge part S8 isset to be small, for example, approximately 10 ml to 100 ml per minute.

Moreover, if the on-off valve 674 is opened, a rinsing liquid 58 (FIG.14) supplied from the rinsing liquid supply source 633 is dischargedfrom the rinsing liquid supply nozzle 627 of the processing liquiddischarging portion 622 and is then supplied to the upper surfaceperipheral edge part S8. Consequently, rinsing for the peripheral edgepart of the substrate W6 is carried out.

FIG. 18 is a view illustrating, in a graph, a difference in temperaturedistribution on the substrate W6 depending on presence or absence of theheating portion 621 (661) for heating the upper surface peripheral edgepart S8 of the substrate W6. A graph 86 shows an example of atemperature distribution on the upper surface S6 of the substrate W6 inthe case where the processing liquid is discharged from a disk-shapednozzle (not shown) provided on the back surface S7 side of the substrateW6 toward the back surface S7 of the substrate W6 which is being rotatedat a predetermined rotating speed for comparison. The processing liquidto be discharged to the back surface S7 has a temperature regulatedpreviously to 90° C. or the like, for example, and is supplied to theperipheral edge part of the substrate W6 by the action of centrifugalforce. A graph 87 shows an example of a temperature distribution on theupper surface S6 of the substrate W6 in the case where the processingliquid is supplied to the back surface S7 in the same manner as in thegraph 86, and furthermore, the upper surface peripheral edge part S8 isheated by the heating portion 621 (661).

As shown in each of the graphs in FIG. 18, the temperature of theprocessing liquid is gradually reduced depending on the rotation of thesubstrate W6 apart from the central part of the substrate W6 so that thetemperature on the upper surface S6 is also reduced. However, in thecase where the upper surface peripheral edge part S8 is also heated bythe heating portion 621 (661), it is possible to raise the temperatureof the upper surface peripheral edge part S8 portion as shown in thegraph 87. The steam is injected in such a manner that the peripheraledge of the upper surface peripheral edge part S8 is spatially exposedto a part of the steam. Therefore, as shown in the graph 87, it ispossible to raise the temperature of a region having a small width of 1mm or less as compared with the other regions of the upper surface S6 ofthe substrate W6 from the peripheral edge of the upper surfaceperipheral edge part S8, for example.

FIG. 19 is a view showing a difference in an etching width over theupper surface S6 of the substrate W6 illustrated in FIG. 20 depending onpresence or absence of operations of the heating portion 621 (661) forheating the upper surface peripheral edge part S8 of the substrate W6and the processing liquid discharging portion 622 for supplying theprocessing liquid to the upper surface peripheral edge part S8. Forconvenience of illustration, each etching width is described to belarger than an actual range.

A substantially circular boundary 46 indicates an example of a boundarybetween an etched region and a non-processed region which is notsubjected to the etching at the rotating axis a6 side in the case wherethe upper surface peripheral edge part S8 is heated by the heatingportion 621 (661), and at the same time, the processing liquid issupplied from the processing liquid supply nozzle 626 to the uppersurface peripheral edge part S8. Moreover, FIG. 21 is a view showing anexample of a sectional view of the substrate W6 obtained after theetching in this case. The processing liquid is not supplied to the backsurface S7 of the substrate W6. A width 26 (FIGS. 19 and 21) indicatesan etching width at one point on the boundary 46. The etching width 26is approximately 0.5 to 1.0 mm, for example, and a variation thereof isreduced to be approximately 1/10 or less of a mean value of the etchingwidth 26, for example.

A boundary 47 indicates an example of a boundary between an etchedregion in the upper surface S6 of the substrate W6 and a non-processedregion in the case where the etching for the upper surface peripheraledge part S8 is carried out with the processing liquid discharged fromthe disk-shaped nozzle (not shown) provided on the back surface S7 sideof the substrate W6 to the back surface S7 of the substrate W6 which isbeing rotated for comparison. FIG. 22 is a view showing an example ofthe sectional view of the substrate W6 obtained after the etching inthis case. The centrifugal force acts on the processing liquiddischarged to the back surface S7 so that the processing liquid spreadstoward the peripheral edge part of the substrate W6, and furthermore,goes around the upper surface peripheral edge part S8. Thus, the uppersurface peripheral edge part S8 is etched. There are carried out neitherthe heating for the upper surface peripheral edge part S8 through theheating portion 621 (661) nor the supply of the processing liquid to theupper surface peripheral edge part S8 through the processing liquiddischarging portion 622.

A width 27 indicates an etching width at one point on the boundary 47.It is difficult to control an amount of the processing liquid goingaround the upper surface peripheral edge part S8 by the action of thecentrifugal force. For this reason, a shape of the boundary 47 is morewavy than the boundary 46 taking the substantially circular shape, andthe etching width 27 is approximately 2 to 3 mm, for example, and islarger than the etching width 26. Moreover, a variation in the etchingwidth 27 is greater than that in the etching width 26.

As shown in FIGS. 19, 21 and 22, in the case where there are carried outthe heating through the heating portion 621 (661) and the supply of theprocessing liquid through the processing liquid discharging portion 622,the etching width in the upper surface peripheral edge part S8 issmaller and the variation in the etching width is also reduced moregreatly as compared with the case where the etching is carried out bythe wraparound of the processing liquid from the back surface S7 side.

As described above, in the substrate processing device 600, theperipheral edge parts are heated in the plurality of different positionsin the rotating track of the peripheral edge parts of the substrate W6respectively so that the processing liquid is supplied to the peripheraledge parts from above. Therefore, even in the case where the heatingwidth in the radial direction of the substrate W6 in the peripheral edgepart is small, the temperature of the peripheral edge part is preventedfrom being reduced. For this reason, even if the amount of theprocessing liquid to be supplied to the peripheral edge part is small,it is possible to suppress reduction in the reaction rate of theprocessing liquid in the region having a small width which is heated bythe heating portion in the peripheral edge part of the upper surface ofthe substrate W6, thereby increasing the reactivity of the processingliquid. Accordingly, it is possible to decrease the chemical treatingwidth while suppressing deterioration in each of the uniformity of thechemical treating width and the processing efficiency.

As shown in FIG. 12, the steam 56 (FIG. 13) is injected from the heatingportion 621 to the upper surface peripheral edge part S8 in apredetermined position (a first position) of the rotating track of theupper surface peripheral edge part S8 of the substrate W6. Then, theprocessing liquid 57 is supplied from the processing liquid dischargingportion 622 to the upper surface peripheral edge part S8 in apredetermined position (a second position) placed behind thepredetermined position along the rotating track. Accordingly, theprocessing liquid 57 is supplied from the processing liquid dischargingportion 622 to the upper surface peripheral edge part S8 portion heatedby the heating portion 621 immediately after the heating. Thereafter,the etching for the portion is carried out. Thus, the reduction in thetemperature of the upper surface peripheral edge part S8 heated by theheating portion 621 is suppressed, and at the same time, the etching forthe upper surface peripheral edge part S8 is carried out. Therefore, theetching rate can be enhanced.

If the plurality of heating portions 621 and 661 are close to each otherin the vicinity of the first position, it is possible to furtherefficiently raise the temperature of the portion to which the processingliquid is supplied from the processing liquid discharging portion 622 inthe second position as compared with the case where the plurality ofheating portions are provided apart from each other as shown in FIG. 12.Accordingly, even if the plurality of heating portions 621 and 661 areclose to each other in the vicinity of the first position, theusefulness of the present invention is not lost.

Moreover, as shown in FIG. 11, a nitrogen gas supply source 634 isprovided on the outside of the substrate processing device 600. As shownin FIGS. 13 to 15, the nitrogen gas is supplied from the nitrogen gassupply source 634 through a pipe 881 to the pipe 684 (694) connected tothe nitrogen gas injecting portion 624 (664) (“the gas injectingportion”) of the substrate processing device 600. An on-off valve 671 tobe on-off controlled by the valve control mechanism 652 is provided inthe middle part of the pipe 881 in the substrate processing device 600.The pipe 881 branches into two parts at the downstream side of theon-off valve 675 (the spin chuck 611 side). One of the branching pipes881 is connected in communication with the pipe 684 and the other isconnected in communication with the pipe 694.

When the control portion 651 opens the on-off valve 671 through thevalve control mechanism 652, the nitrogen gas is supplied from thenitrogen gas supply source 634 to the nitrogen gas injecting portion 624(664). The nitrogen gas injecting portion 624 (664) is configured tohave a slender arcuate sectional shape in a circumferential direction ofthe substrate W6, for example. The nitrogen gas injection nozzle 628(668) is configured by an injection nozzle having a slender arc-shapedopening in the circumferential direction of the substrate W6 on a lowersurface of the nitrogen gas injecting portion 624 (664), a plurality ofcylindrical injection nozzles provided at a predetermined interval onthe lower surface of the nitrogen gas injecting portion 624 (664) or thelike. The nitrogen gas supplied to the nitrogen gas injecting portion624 (664) is injected as a nitrogen gas G6 (a gas for purge) from thenitrogen gas injection nozzle 628 (668) to the upper surface S6 of therotating substrate W6.

In more detail, a nitrogen gas G6 is injected from the nitrogen gasinjection nozzle 628 (668) provided above the substrate W6 toward apredetermined injection target region defined within a range surroundedby the rotating track of the upper surface peripheral edge part S8 inthe upper surface S6 of the substrate W6. Then, the nitrogen gas G6injected onto the upper surface S6 forms a gas flow which flows from theinjection target region toward the upper surface peripheral edge part S8of the substrate W6. Mist obtained by the condensation of the steam 56injected from the heating portion 621 (661) to the upper surfaceperipheral edge part S8 through the air flow formed by the nitrogen gasG6, the processing liquid 57 discharged from the processing liquidsupply nozzle 626 of the processing liquid discharging portion 622, orthe like can be prevented from adhering onto the non-processed region inthe upper surface S6 of the substrate W6 in which the etching is notcarried out. Therefore, it is possible to supply a sufficient amount ofsteam for heating the peripheral edge part of the substrate W6 whilesuppressing deterioration in the non-processed region due to theadhering of the mist.

Moreover, also in a drying treatment for the upper surface S6 of thesubstrate W6 after the end of the rinsing, the substrate W6 is promotedto be dried with the nitrogen gas G6 supplied from the nitrogen gasinjection nozzle 628 (668), and furthermore, the rinsing liquid shakenoff from the upper surface peripheral edge part S8 toward the outside ofthe substrate W6 by the centrifugal force acting through the high-speedrotation of the substrate W6 can be prevented from returning to thesubstrate W6 and adhering onto the non-processed region of the uppersurface S6. Even if the substrate processing device 600 includes neitherthe nitrogen gas supply source 634 nor the nitrogen gas injectingportions 624 and 664, it is possible to reduce the etching width whilesuppressing deterioration in each of the uniformity of the etching widthand the etching rate. Therefore, the usefulness of the present inventionis not lost.

<4. Operation of Substrate Processing Device>

FIG. 23 is a flow chart showing an example of a flow of substrateprocessing to be carried out by the substrate processing device 600according to the second preferred embodiment. Before the start of theprocessing, each of the on-off valves is closed and the spin chuck 611is stationary. Moreover, the nozzle units 620 and 660 are placed instandby positions other than the delivery-in path for the substrate W6.First of all, the single substrate W6 is delivered by a substratedelivery robot (not shown) into a processing chamber (chamber) (notshown) in which the spin chuck 611 is disposed, and is mounted on thespin chuck 611 to be held by the chuck pin 617 (step S610).

Subsequently, the nozzle units 620 and 660 are placed in predeterminedpositions above the upper surface peripheral edge part S8 of thesubstrate W6. Then, the on-off valve 671 is opened and the nitrogen gasinjecting portions 624 and 664 inject, as the nitrogen gas G6 (the gasfor purge), the nitrogen gas supplied from the nitrogen gas supplysource 634 toward the upper surface peripheral edge part S8 of thesubstrate W6 (step S620).

Next, the control portion 651 controls the chuck rotating mechanism 654so that the rotation of the spin chuck 611 is started in such a mannerthat the rotating speed of the spin chuck 611 becomes a predeterminedhigh rotating speed of 50 rpm to 800 rpm, for example (step S630). Then,the on-off valve 675 is opened and the heating steam generated by thesteam supply source 631 and heated by the heater 639 is supplied to thenozzle units 620 and 660. The nozzle units 620 and 660 start to injectthe heating steam from the steam injection nozzles 625 and 665 towardthe region having a small width at the peripheral edge side of the uppersurface peripheral edge part S8 (step S640), thereby starting to heatthe upper surface peripheral edge part S8. The heating steam is injectedfrom the steam injection nozzles 625 and 665 in such a manner that theupper surface peripheral edge part S8 is spatially exposed to a part ofthe heating steam.

Subsequently, the etching for the upper surface peripheral edge part S8of the substrate W6 is carried out (step S650). More specifically, theon-off valve 673 is opened so that the processing liquid is suppliedfrom the processing liquid supply source 632 to the processing liquiddischarging portion 622 of the nozzle unit 620 and discharged from theprocessing liquid supply nozzle 626 to a narrow width region at theperipheral edge side of the upper surface peripheral edge part S8 whichis heated. Then, the etching for the upper surface peripheral edge partS8 of the substrate W6 is carried out with the discharged processingliquid.

When a predetermined time elapsed and the etching for the upper surfaceperipheral edge part S8 is completed, the on-off valve 673 is closed sothat the supply of the processing liquid to the substrate W6 is stopped.Thereafter, the on-off valve 675 is closed so that the injection of theheating steam is stopped (step S660).

Subsequently, the rinsing for the upper surface peripheral edge part S8of the substrate W6 is carried out (step S670). More specifically, theon-off valve 674 is opened and the rinsing liquid is started to besupplied from the rinsing liquid supply source 633. Then, the rinsingliquid is discharged from the rinsing liquid supply nozzle 627 of theprocessing liquid discharging portion 622 to the upper surfaceperipheral edge part S8 so that the rinsing for the upper surfaceperipheral edge part S8 is carried out. When a predetermined timeelapsed and the rinsing for the upper surface peripheral edge part S8 iscompleted, the on-off valve 674 is closed so that the supply of therinsing liquid is stopped.

Next, the rotation of the spin chuck 611 is continuously carried out fora predetermined time in a state in which the rotating speed of the spinchuck 611 is set to be a high rotating speed of 1000 rpm to 1500 rpm.Consequently, the rinsing liquid remaining in the upper surfaceperipheral edge part S8 is shaken off toward the outside of thesubstrate W6 by the action of centrifugal force so that a dryingtreatment (spin drying) for the upper surface S6 of the substrate W6 iscarried out (step S680). In the spin drying, the nitrogen gas G6 iscontinuously supplied from the nitrogen gas injection nozzles 628 and668 of the nitrogen gas injecting portions 624 and 664 to the uppersurface peripheral edge part S8. Consequently, drying of the rinsingliquid adhering onto the upper surface peripheral edge part S8 ispromoted, and furthermore, the shaken-off rinsing liquid can beprevented from returning to the substrate W6 side and adhering onto thenon-processed region of the upper surface S6.

When a predetermined time elapsed since the start of the dryingtreatment, the rotation of the spin chuck 611 is stopped so that thedrying treatment is ended (step S690). Subsequently, the on-off valve671 is closed so that the injection of the nitrogen gas G6 (the gas forpurge) from the nitrogen gas injecting portions 624 and 664 is stopped(step S700).

When the injection of the gas from the nitrogen gas injecting portions624 and 664 is stopped, the control portion 651 controls the nozzlerotating mechanisms 655 and 656 to move the nozzle units 620 and 660 tothe standby positions. Then, the processed substrate W6 is removed fromthe spin chuck 611 and is thus delivered to the outside of theprocessing chamber by means of a delivery robot (not shown) (step S710)so that the substrate processing to be carried out by the substrateprocessing device 600 is ended.

According to the substrate processing device in accordance with thesecond preferred embodiment configured as described above, theperipheral edge parts are heated in the plurality of different positionsin the rotating track of the peripheral edge parts of the substrate W6respectively so that the processing liquid is supplied to the peripheraledge parts from above. Consequently, even in the case where the heatingwidth in the radial direction in the peripheral edge part is small, thetemperature of the peripheral edge part is prevented from being reduced.Even if the amount of the processing liquid to be supplied to theperipheral edge part is small, it is possible to suppress reduction inthe reaction rate of the processing liquid in the region having a smallwidth at the peripheral edge side which is heated by the heating portionin the peripheral edge part of the upper surface S6 of the substrate W6,thereby increasing the reactivity of the processing liquid. Accordingly,it is possible to decrease the chemical treating width while suppressingdeterioration in each of the uniformity of the chemical treating width(the etching width) and the processing efficiency.

Moreover, according to the substrate processing device in accordancewith the second preferred embodiment configured as described above, itis also possible to implement the plurality of heating portions byincluding at least one of the thermal fluid supplying portion forsupplying, to the peripheral edge part of the substrate W6, the heatedfluid which is made of the material having no chemical reactivity to thesubstance which is present in the peripheral edge part, thereby heatingthe peripheral edge part, and the light irradiating portion forirradiating the peripheral edge part of the substrate W6 with light toheat the peripheral edge part. The peripheral edge part of the substrateW6 is spatially exposed to a part of the heated fluid and the light.Accordingly, it is possible to reduce the heating width of the uppersurface peripheral edge part S8 more greatly while heating the uppersurface peripheral edge part S8 efficiently. Therefore, in the casewhere the etchant (the processing liquid) having a reaction rateincreased with a rise in temperature is used, it is possible to decreasethe etching width (the chemical treating width) by reducing the heatingwidth of the upper surface peripheral edge part S8.

Furthermore, according to the substrate processing device in accordancewith the second preferred embodiment configured as described above, theheating steam is injected as the heating fluid from each of theplurality of heating portions to the peripheral edge part of thesubstrate W6 to heat the peripheral edge part. Accordingly, as comparedwith the case where the upper surface peripheral edge part S8 is heatedwith light emitted from a halogen lamp or the like, it is possible toheat the upper surface peripheral edge part S8 more efficiently.Moreover, differently from the case where light is used, glass is notrequired in the heating portion. For this reason, continuous use for along period of time is possible even in the case where a processingliquid having reactivity to the glass is used.

Furthermore, according to the substrate processing device in accordancewith the second preferred embodiment configured as described above, thesuperheated steam having the high temperature is used as the heatingsteam. For this reason, the steam can be maintained at a hightemperature even after being injected from the steam injection nozzleand used for heating the upper surface peripheral edge part S8.Consequently, it is possible to prevent the steam from being changedinto mist in the peripheral edge part. Therefore, the mist obtained bythe condensation of the steam can be prevented from adhering onto thenon-processed region of the substrate W6. Moreover, if the superheatedsteam having a high temperature is thus used, it is possible to raisethe temperature of the upper surface peripheral edge part S8 of thesubstrate W6 more greatly as compared with the case where saturatedsteam having a temperature of 100° C. or less is used in the heattreatment, for example. Consequently, it is possible to increase theetching rate more greatly.

Moreover, according to the substrate processing device in accordancewith the second preferred embodiment configured as described above, theheating steam is injected through each of the steam injection nozzles tothe peripheral edge part along the injection path in the obliquelydownward direction from the inside of the substrate W6 toward theoutside thereof. Consequently, there is generated a gas flow of thesteam which flows from the upper surface peripheral edge part S8 of thesubstrate W6 toward the outside of the substrate W6. Therefore, the mistobtained by the condensation of the steam can be prevented from adheringonto the non-processed region of the upper surface S6 of the substrateW6 due to return to the substrate W6 side.

Furthermore, according to the substrate processing device in accordancewith the second preferred embodiment configured as described above, thegas (the nitrogen gas G6) is injected from above the substrate W6 towardthe predetermined injection target region defined within the rangesurrounded by the rotating track of the upper surface peripheral edgepart S8 of the substrate W6 in the upper surface S6 of the substrate W6.Consequently, there is generated, on the substrate W6, the gas flowwhich flows from the injection target region toward the upper surfaceperipheral edge part S8 of the substrate W6. Therefore, the mistobtained by the condensation of the steam or the mist-like processingliquid can be prevented from adhering onto the non-processed region inthe upper surface S6 of the substrate W6. Accordingly, it is possible tosupply a sufficient amount of steam for heating the peripheral edge partS8 of the substrate W6 while inhibiting the non-processed region frombeing deteriorated by the adhering of the mist.

In the substrate processing device 600, for example, a nitrogen gasheating portion may further be provided in the pipe 881 for supplyingthe nitrogen gas G6 from the nitrogen gas supply source 634 to thenitrogen gas injecting portion 624 (664) in such a manner that theheated nitrogen gas G6 is supplied to the upper surface peripheral edgepart S8 of the substrate W6. If the heated nitrogen gas G6 is supplied,the etching rate can further be enhanced. Moreover, the nitrogen gassupply source 634 or the steam supply source 631 may be provided in thesubstrate processing device 600, for example. It is also possible toemploy a structure in which a dry gas such as dry air or an inert gasother than the nitrogen gas is supplied in place of the supply of thenitrogen gas through the nitrogen gas supply source 634. Moreover,although the respective nozzles or the like in the nozzle units 620 and660 are moved integrally with the substrate W6, they may be configuredto be individually movable.

While the invention has been shown and described in detail, theforegoing description is in all aspects illustrative and notrestrictive. It is therefore understood that numerous modifications andvariations can be devised without departing from the scope of theinvention.

What is claimed is:
 1. A substrate processing device for carrying out achemical treatment for a substrate by using a processing liquid having achemical activity varied depending on a temperature, the devicecomprising: a substrate holding portion for holding a substrate in asubstantially horizontal posture; a rotating portion for rotating saidsubstrate held in said substrate holding portion in a substantiallyhorizontal plane; a heating portion for injecting heating steam to aperipheral edge part of said substrate to heat said peripheral edgepart; a peripheral edge processing portion for supplying a processingliquid from above to said peripheral edge part heated by said heatingportion, thereby carrying out a chemical treatment for said peripheraledge part; and a gas injecting portion for injecting a gas from abovesaid substrate toward a predetermined injection target region definedwithin a range surrounded by a rotating track of said peripheral edgepart of said substrate in an upper surface of said substrate, togenerate, on the substrate, a gas flow which flows from said injectiontarget region toward said peripheral edge part of said substrate.
 2. Thesubstrate processing device according to claim 1, further comprising alower surface processing portion for supplying a processing liquid to alower surface of said substrate, thereby carrying out a chemicaltreatment for the lower surface, said lower surface processing portionincluding an opposed surface which is opposed to a substantially entireregion of the lower surface of said substrate which is rotated by saidrotating portion and a processing liquid discharging port formed on saidopposed surface, and discharging the processing liquid from saidprocessing liquid discharging port to bring a space between the lowersurface of said substrate and said opposed surface to a fluid-tightcondition with the processing liquid.
 3. The substrate processing deviceaccording to claim 2, wherein said opposed surface takes a shape of afunnel in which said processing liquid discharging port portion has agreater interval from the lower surface of said substrate than a portionopposed to said peripheral edge part.
 4. The substrate processing deviceaccording to claim 1, wherein said heating portion and said peripheraledge processing portion are provided in a positional relationship inwhich said steam from said heating portion is injected to saidperipheral edge part in a first position of a rotating track of saidperipheral edge part of said substrate, and said processing liquid fromsaid peripheral edge processing portion is supplied to said peripheraledge part in a second position placed behind said first position alongsaid rotating track.
 5. A substrate processing device for carrying out achemical treatment for a substrate by using a processing liquid having areaction rate increased with a rise in temperature, the devicecomprising: a substrate holding portion for holding a substrate in asubstantially horizontal posture; a rotating portion for rotating saidsubstrate held in said substrate holding portion in a substantiallyhorizontal plane; a plurality of heating portions disposed to be opposedto a plurality of different positions in a rotating track of aperipheral edge part of said substrate respectively and heating saidperipheral edge part in said plurality of positions respectively; and aperipheral edge processing portion for supplying the processing liquidfrom above to said peripheral edge part heated by said plurality ofheating portions, thereby carrying out a chemical treatment for saidperipheral edge part.
 6. The substrate processing device according toclaim 5, wherein said plurality of heating portions include at least oneof: (1) a thermal fluid supplying portion for supplying a heated fluidto said peripheral edge part of said substrate; and (2) a lightirradiating portion for irradiating said peripheral edge part of saidsubstrate with light, said peripheral edge part of said substrate isspatially exposed to a part of said heated fluid and said light, andsaid heated fluid is made of a material having no chemical reactivity toa substance which is present in said peripheral edge part of saidsubstrate.
 7. The substrate processing device according to claim 6,wherein each of said plurality of heating portions injects heating steamas said heated fluid to said plurality of positions to heat saidperipheral edge part respectively.
 8. The substrate processing deviceaccording to claim 7, wherein said steam is superheated steam.
 9. Thesubstrate processing device according to claim 7, wherein said pluralityof heating portions inject said steam to said peripheral edge part alongan injection path in an obliquely downward direction from an inside ofsaid substrate toward an outside thereof, respectively.
 10. Thesubstrate processing device according to claim 7, further comprising agas injecting portion for injecting a gas from above said substratetoward a predetermined injection target region defined within a rangesurrounded by a rotating track of said peripheral edge part of saidsubstrate in an upper surface of said substrate, to generate, on thesubstrate, a gas flow which flows from said injection target regiontoward said peripheral edge part of said substrate.
 11. A substrateprocessing method for carrying out a chemical treatment for a substrateby using a processing liquid having a chemical activity varied dependingon a temperature, the method comprising: a rotating step of holding asubstrate in a substantially horizontal posture to rotate the substratein a substantially horizontal plane; a heating step of injecting heatingsteam to a peripheral edge part of said substrate to heat the peripheraledge part in parallel with said rotating step; a peripheral edgeprocessing step of supplying a processing liquid from above to saidperipheral edge part which is heated in said heating step, therebycarrying out a chemical treatment for said peripheral edge part; and agas injecting step of injecting a gas from above said substrate toward apredetermined injection target region defined within a range surroundedby a rotating track of said peripheral edge part of said substrate in anupper surface of said substrate, to generate, on the substrate, a gasflow which flows from said injection target region toward saidperipheral edge part of said substrate in parallel with said heatingstep and said peripheral edge processing step.